Actually my aim is to create a "traffic" animation from side view. 2D.
And i want my cars(dots in this case) to move from left to right appearing at the very left edge of the stage and disappearing at the very right edge regardless the width of the stage. And travelling the stage with a constant speed again regardless of the total width.
If i give x a value of zero to make them generate at the far left side of the stage, then all the dynamically created movieclips overlap and act as one dot.